Studied Space Shuttle designs
Various Heavy Lift Launch Vehicle concepts were investigated between 1984 and 1995 and it would eventually become known as the Shuttle-C, which lacked reusable engines and ballistic return pods.
[2]The Magnum was a large Super heavy-lift launch vehicle designed by NASA's Marshall Space Flight Center during the mid-1990s.
Some designs had strap-on boosters using wings and jet engines, which would enable them to fly back to the launch area after they were jettisoned in flight.
[4] Early studies looked at alternate booster and external tank configurations such as: NASA had planned on replacing the post-Challenger SRBs with a new Advanced Solid Rocket Motor (ASRM) to be built by Aerojet.
They would have been built at a new facility designed by a subcontractor, RUST International, on the location of a canceled Tennessee Valley Authority nuclear power plant in Yellow Creek, Mississippi.
The ASRM would have produced additional thrust in order to increase the shuttle payload to carry modules and construction components to the ISS.
The ASRM program was canceled in 1993, after robotic assembly systems and computers were on-site and approximately 2 billion dollars spent, after NASA opted to instead issue minor corrections to the existing SRBs.
The boosters would have a similar flight path to the solid rocket motors, separating and deploying a parachute for recovery in the Atlantic Ocean.
The Shuttle Growth Study built on this background by developing design concepts in great detail for the liquid rocket boosters.
The 5-segment SRB, which would have required little change to the current shuttle infrastructure, would have allowed the space shuttle to carry an additional 20,000 lb (9,100 kg) of payload in a 51.6°-inclination orbit, eliminate the dangerous "Return-to-Launch Site" (RTLS) and "Trans-Oceanic Abort" (TAL) modes, and, by using a so-called "dog-leg maneuver", fly south-to-north polar orbiting flights from Kennedy Space Center.
After the destruction of Columbia, NASA shelved the five-segment SRB for the Shuttle Program, and the three surviving Orbiters, Discovery, Atlantis, and Endeavour were retired in 2011 after the completion of the International Space Station.
These studies were eventually abandoned due to the fact that the new aerodynamic profile would make a Return to Launch Site (RTLS) maneuver impossible.
This would result in a "humpback" outsize cargo vehicle similar to the Airbus Beluga or the Aero Spacelines Super Guppy.
The hypersonic aerodynamic characteristics during re-entry would stay mostly the same however issues would have most likely occurred at subsonic speeds without a high angle of attack.
A payload bay segment would be added to the rear of the spacecraft and look very similar to the Space Shuttle Enterprise albeit with a few differences.
The concept used a series of canisters mounted in the payload bay that would carry 68 to 74 passengers in a double-deck configuration similar to a Boeing 747.
